Zoomlion ZT20J, Service And Maintenance Manual

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5-11
b. Remove the work platform, jib, energy chain, leveling cylinder and hood, please follow the removal
steps.
c. Fully retract the boom.
d. Use suitable wood to support the rear link (cross the wood across the turntable and place it between
the turntable and the rear link).
e. Use suitable wood to support the front link (cross the wood across the turntable and place it between
the turntable and the front link).
f. Slowly lower the boom's lifting angle until the front and rear links are in contact with the wood. Do
not support all the weight of the boom assembly by wood. Turn off the device.
g. Use suitable lifting equipment (lifting weight greater than 7t/15432lb) to connect the lifting point of
the counterweight to support the counterweight.
h. Loosen the bolts connecting the counterweight to the turntable, slowly and carefully remove the
counterweight from the equipment, and place it on the hard ground reliably.
Figure 5-9 Disassembly of the boom assembly
a. Mark and disconnect the wiring harness connected to the sensor and the hydraulic pipeline connected
to the oil cylinder in the boom, collect the hydraulic oil in the pipeline with a suitable container, and
block the port of the pipeline after the collection.
b. Use suitable lifting equipment (lifting weight greater than 5t/11023lb) to support the head and tail of
the boom.But no lifting force is applied.
c. Use appropriate lifting equipment to support the luffing cylinder near the piston rod end and protect
it from damage.
d. Remove pin 1.
Extrusion hazard.When the lifting cylinder piston rod end pin shaft is removed, if the boom support
fails, the boom will fall down, causing personal injury and equipment damage.When removing this
pin, keep personnel away from the area under the boom.